Interstellar Travel

36% of Americans believe in UFOs, that is, though most Unidentified Aerial Phenomena are actually explained as such mundane things as misidentified meteorological phenomena, astronomical phenomena, aircraft, and so on, there's ~ 5% that are as yet unexplained and that these unexplained UFOs are machines from somewhere other than Earth.

Have you ever observed a UFO that has never been sufficiently explained? Do you believe that some unexplained UFOs are machines from somewhere other than Earth? If so, why (what are your reasons or arguments for believing so)? What evidence is there to support your belief?

That it may be, but it's not of much interest to the average person yet because it's just something we know, it's not something that's become part of our everyday lives outside academia. I still think my grandmother's generation experienced the greatest technological changes in their lifetime. Horse-drawn transportation to a man on the moon is hard to beat. She also saw her world go from lantern light and gaslight to nationwide electrification, with all of the changes that brought with it. When she was a child, there wasn't even radio. A handwritten letter would take weeks to go from coast to coast. When she died, with airmail, a letter could go coast to coast in a day and through the miracle of the telegram, information could go almost anywhere in the civilized world almost instantaneously.

Not to be too critical but it is unlikely that a satisfactory example can be provided to your question since the parameters of what would be needed to provide that answer are unclear.

For example: "greatest technological changes" means what?

By what measure? Starting from what basis? Who decides?

You said a couple of things above that seem to me to be contradictory;

"part of our everyday lives"

"greatest technological changes in their lifetime"

you give as an example the changes in transportation ie. buggy to space craft.

So I feel compelled to consider how much of that "technological change" your grandmother experienced as a "part of her everyday life".

Am I correct that she was not an astronaut and had no direct experience with space flight?

I would venture to say that the biggest effect on most of her generation in their "everyday life" was going from buggy to automobile, correct? For some maybe from flying in a prop driven plane to flying in a jet propelled plane.

These are indeed big changes but are they the "greatest technological changes" every to occur in "any" generation?

In my generation and yours we have seen in communication far greater technological advancements by orders of magnitude over what her generation experienced in transportation.

So without objective conditions/requirements to measure and test I see no way anyone can provide you with a satisfactory example that would sway you from your position.